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Commit | Line | Data |
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40b0b3f8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * lib/bitmap.c | |
4 | * Helper functions for bitmap.h. | |
1da177e4 | 5 | */ |
8bc3bcc9 PG |
6 | #include <linux/export.h> |
7 | #include <linux/thread_info.h> | |
1da177e4 LT |
8 | #include <linux/ctype.h> |
9 | #include <linux/errno.h> | |
10 | #include <linux/bitmap.h> | |
11 | #include <linux/bitops.h> | |
50af5ead | 12 | #include <linux/bug.h> |
e52bc7c2 | 13 | #include <linux/kernel.h> |
ce1091d4 | 14 | #include <linux/mm.h> |
c42b65e3 | 15 | #include <linux/slab.h> |
e52bc7c2 | 16 | #include <linux/string.h> |
13d4ea09 | 17 | #include <linux/uaccess.h> |
5aaba363 SH |
18 | |
19 | #include <asm/page.h> | |
1da177e4 | 20 | |
e371c481 YN |
21 | #include "kstrtox.h" |
22 | ||
7d7363e4 RD |
23 | /** |
24 | * DOC: bitmap introduction | |
25 | * | |
1da177e4 LT |
26 | * bitmaps provide an array of bits, implemented using an an |
27 | * array of unsigned longs. The number of valid bits in a | |
28 | * given bitmap does _not_ need to be an exact multiple of | |
29 | * BITS_PER_LONG. | |
30 | * | |
31 | * The possible unused bits in the last, partially used word | |
32 | * of a bitmap are 'don't care'. The implementation makes | |
33 | * no particular effort to keep them zero. It ensures that | |
34 | * their value will not affect the results of any operation. | |
35 | * The bitmap operations that return Boolean (bitmap_empty, | |
36 | * for example) or scalar (bitmap_weight, for example) results | |
37 | * carefully filter out these unused bits from impacting their | |
38 | * results. | |
39 | * | |
1da177e4 LT |
40 | * The byte ordering of bitmaps is more natural on little |
41 | * endian architectures. See the big-endian headers | |
42 | * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h | |
43 | * for the best explanations of this ordering. | |
44 | */ | |
45 | ||
1da177e4 | 46 | int __bitmap_equal(const unsigned long *bitmap1, |
5e068069 | 47 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 48 | { |
5e068069 | 49 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
50 | for (k = 0; k < lim; ++k) |
51 | if (bitmap1[k] != bitmap2[k]) | |
52 | return 0; | |
53 | ||
54 | if (bits % BITS_PER_LONG) | |
55 | if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
56 | return 0; | |
57 | ||
58 | return 1; | |
59 | } | |
60 | EXPORT_SYMBOL(__bitmap_equal); | |
61 | ||
b9fa6442 TG |
62 | bool __bitmap_or_equal(const unsigned long *bitmap1, |
63 | const unsigned long *bitmap2, | |
64 | const unsigned long *bitmap3, | |
65 | unsigned int bits) | |
66 | { | |
67 | unsigned int k, lim = bits / BITS_PER_LONG; | |
68 | unsigned long tmp; | |
69 | ||
70 | for (k = 0; k < lim; ++k) { | |
71 | if ((bitmap1[k] | bitmap2[k]) != bitmap3[k]) | |
72 | return false; | |
73 | } | |
74 | ||
75 | if (!(bits % BITS_PER_LONG)) | |
76 | return true; | |
77 | ||
78 | tmp = (bitmap1[k] | bitmap2[k]) ^ bitmap3[k]; | |
79 | return (tmp & BITMAP_LAST_WORD_MASK(bits)) == 0; | |
80 | } | |
81 | ||
3d6684f4 | 82 | void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) |
1da177e4 | 83 | { |
ca1250bb | 84 | unsigned int k, lim = BITS_TO_LONGS(bits); |
1da177e4 LT |
85 | for (k = 0; k < lim; ++k) |
86 | dst[k] = ~src[k]; | |
1da177e4 LT |
87 | } |
88 | EXPORT_SYMBOL(__bitmap_complement); | |
89 | ||
72fd4a35 | 90 | /** |
1da177e4 | 91 | * __bitmap_shift_right - logical right shift of the bits in a bitmap |
05fb6bf0 RD |
92 | * @dst : destination bitmap |
93 | * @src : source bitmap | |
94 | * @shift : shift by this many bits | |
2fbad299 | 95 | * @nbits : bitmap size, in bits |
1da177e4 LT |
96 | * |
97 | * Shifting right (dividing) means moving bits in the MS -> LS bit | |
98 | * direction. Zeros are fed into the vacated MS positions and the | |
99 | * LS bits shifted off the bottom are lost. | |
100 | */ | |
2fbad299 RV |
101 | void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, |
102 | unsigned shift, unsigned nbits) | |
1da177e4 | 103 | { |
cfac1d08 | 104 | unsigned k, lim = BITS_TO_LONGS(nbits); |
2fbad299 | 105 | unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
cfac1d08 | 106 | unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); |
1da177e4 LT |
107 | for (k = 0; off + k < lim; ++k) { |
108 | unsigned long upper, lower; | |
109 | ||
110 | /* | |
111 | * If shift is not word aligned, take lower rem bits of | |
112 | * word above and make them the top rem bits of result. | |
113 | */ | |
114 | if (!rem || off + k + 1 >= lim) | |
115 | upper = 0; | |
116 | else { | |
117 | upper = src[off + k + 1]; | |
cfac1d08 | 118 | if (off + k + 1 == lim - 1) |
1da177e4 | 119 | upper &= mask; |
9d8a6b2a | 120 | upper <<= (BITS_PER_LONG - rem); |
1da177e4 LT |
121 | } |
122 | lower = src[off + k]; | |
cfac1d08 | 123 | if (off + k == lim - 1) |
1da177e4 | 124 | lower &= mask; |
9d8a6b2a RV |
125 | lower >>= rem; |
126 | dst[k] = lower | upper; | |
1da177e4 LT |
127 | } |
128 | if (off) | |
129 | memset(&dst[lim - off], 0, off*sizeof(unsigned long)); | |
130 | } | |
131 | EXPORT_SYMBOL(__bitmap_shift_right); | |
132 | ||
133 | ||
72fd4a35 | 134 | /** |
1da177e4 | 135 | * __bitmap_shift_left - logical left shift of the bits in a bitmap |
05fb6bf0 RD |
136 | * @dst : destination bitmap |
137 | * @src : source bitmap | |
138 | * @shift : shift by this many bits | |
dba94c25 | 139 | * @nbits : bitmap size, in bits |
1da177e4 LT |
140 | * |
141 | * Shifting left (multiplying) means moving bits in the LS -> MS | |
142 | * direction. Zeros are fed into the vacated LS bit positions | |
143 | * and those MS bits shifted off the top are lost. | |
144 | */ | |
145 | ||
dba94c25 RV |
146 | void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, |
147 | unsigned int shift, unsigned int nbits) | |
1da177e4 | 148 | { |
dba94c25 | 149 | int k; |
7f590657 | 150 | unsigned int lim = BITS_TO_LONGS(nbits); |
dba94c25 | 151 | unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; |
1da177e4 LT |
152 | for (k = lim - off - 1; k >= 0; --k) { |
153 | unsigned long upper, lower; | |
154 | ||
155 | /* | |
156 | * If shift is not word aligned, take upper rem bits of | |
157 | * word below and make them the bottom rem bits of result. | |
158 | */ | |
159 | if (rem && k > 0) | |
6d874eca | 160 | lower = src[k - 1] >> (BITS_PER_LONG - rem); |
1da177e4 LT |
161 | else |
162 | lower = 0; | |
7f590657 | 163 | upper = src[k] << rem; |
6d874eca | 164 | dst[k + off] = lower | upper; |
1da177e4 LT |
165 | } |
166 | if (off) | |
167 | memset(dst, 0, off*sizeof(unsigned long)); | |
168 | } | |
169 | EXPORT_SYMBOL(__bitmap_shift_left); | |
170 | ||
f4b0373b | 171 | int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 172 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 173 | { |
2f9305eb | 174 | unsigned int k; |
7e5f97d1 | 175 | unsigned int lim = bits/BITS_PER_LONG; |
f4b0373b | 176 | unsigned long result = 0; |
1da177e4 | 177 | |
7e5f97d1 | 178 | for (k = 0; k < lim; k++) |
f4b0373b | 179 | result |= (dst[k] = bitmap1[k] & bitmap2[k]); |
7e5f97d1 RV |
180 | if (bits % BITS_PER_LONG) |
181 | result |= (dst[k] = bitmap1[k] & bitmap2[k] & | |
182 | BITMAP_LAST_WORD_MASK(bits)); | |
f4b0373b | 183 | return result != 0; |
1da177e4 LT |
184 | } |
185 | EXPORT_SYMBOL(__bitmap_and); | |
186 | ||
187 | void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, | |
2f9305eb | 188 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 189 | { |
2f9305eb RV |
190 | unsigned int k; |
191 | unsigned int nr = BITS_TO_LONGS(bits); | |
1da177e4 LT |
192 | |
193 | for (k = 0; k < nr; k++) | |
194 | dst[k] = bitmap1[k] | bitmap2[k]; | |
195 | } | |
196 | EXPORT_SYMBOL(__bitmap_or); | |
197 | ||
198 | void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, | |
2f9305eb | 199 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 200 | { |
2f9305eb RV |
201 | unsigned int k; |
202 | unsigned int nr = BITS_TO_LONGS(bits); | |
1da177e4 LT |
203 | |
204 | for (k = 0; k < nr; k++) | |
205 | dst[k] = bitmap1[k] ^ bitmap2[k]; | |
206 | } | |
207 | EXPORT_SYMBOL(__bitmap_xor); | |
208 | ||
f4b0373b | 209 | int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, |
2f9305eb | 210 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 211 | { |
2f9305eb | 212 | unsigned int k; |
74e76531 | 213 | unsigned int lim = bits/BITS_PER_LONG; |
f4b0373b | 214 | unsigned long result = 0; |
1da177e4 | 215 | |
74e76531 | 216 | for (k = 0; k < lim; k++) |
f4b0373b | 217 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); |
74e76531 RV |
218 | if (bits % BITS_PER_LONG) |
219 | result |= (dst[k] = bitmap1[k] & ~bitmap2[k] & | |
220 | BITMAP_LAST_WORD_MASK(bits)); | |
f4b0373b | 221 | return result != 0; |
1da177e4 LT |
222 | } |
223 | EXPORT_SYMBOL(__bitmap_andnot); | |
224 | ||
30544ed5 AS |
225 | void __bitmap_replace(unsigned long *dst, |
226 | const unsigned long *old, const unsigned long *new, | |
227 | const unsigned long *mask, unsigned int nbits) | |
228 | { | |
229 | unsigned int k; | |
230 | unsigned int nr = BITS_TO_LONGS(nbits); | |
231 | ||
232 | for (k = 0; k < nr; k++) | |
233 | dst[k] = (old[k] & ~mask[k]) | (new[k] & mask[k]); | |
234 | } | |
235 | EXPORT_SYMBOL(__bitmap_replace); | |
236 | ||
1da177e4 | 237 | int __bitmap_intersects(const unsigned long *bitmap1, |
6dfe9799 | 238 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 239 | { |
6dfe9799 | 240 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
241 | for (k = 0; k < lim; ++k) |
242 | if (bitmap1[k] & bitmap2[k]) | |
243 | return 1; | |
244 | ||
245 | if (bits % BITS_PER_LONG) | |
246 | if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
247 | return 1; | |
248 | return 0; | |
249 | } | |
250 | EXPORT_SYMBOL(__bitmap_intersects); | |
251 | ||
252 | int __bitmap_subset(const unsigned long *bitmap1, | |
5be20213 | 253 | const unsigned long *bitmap2, unsigned int bits) |
1da177e4 | 254 | { |
5be20213 | 255 | unsigned int k, lim = bits/BITS_PER_LONG; |
1da177e4 LT |
256 | for (k = 0; k < lim; ++k) |
257 | if (bitmap1[k] & ~bitmap2[k]) | |
258 | return 0; | |
259 | ||
260 | if (bits % BITS_PER_LONG) | |
261 | if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) | |
262 | return 0; | |
263 | return 1; | |
264 | } | |
265 | EXPORT_SYMBOL(__bitmap_subset); | |
266 | ||
877d9f3b | 267 | int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) |
1da177e4 | 268 | { |
877d9f3b RV |
269 | unsigned int k, lim = bits/BITS_PER_LONG; |
270 | int w = 0; | |
1da177e4 LT |
271 | |
272 | for (k = 0; k < lim; k++) | |
37d54111 | 273 | w += hweight_long(bitmap[k]); |
1da177e4 LT |
274 | |
275 | if (bits % BITS_PER_LONG) | |
37d54111 | 276 | w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits)); |
1da177e4 LT |
277 | |
278 | return w; | |
279 | } | |
1da177e4 LT |
280 | EXPORT_SYMBOL(__bitmap_weight); |
281 | ||
e5af323c | 282 | void __bitmap_set(unsigned long *map, unsigned int start, int len) |
c1a2a962 AM |
283 | { |
284 | unsigned long *p = map + BIT_WORD(start); | |
fb5ac542 | 285 | const unsigned int size = start + len; |
c1a2a962 AM |
286 | int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); |
287 | unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); | |
288 | ||
fb5ac542 | 289 | while (len - bits_to_set >= 0) { |
c1a2a962 | 290 | *p |= mask_to_set; |
fb5ac542 | 291 | len -= bits_to_set; |
c1a2a962 AM |
292 | bits_to_set = BITS_PER_LONG; |
293 | mask_to_set = ~0UL; | |
294 | p++; | |
295 | } | |
fb5ac542 | 296 | if (len) { |
c1a2a962 AM |
297 | mask_to_set &= BITMAP_LAST_WORD_MASK(size); |
298 | *p |= mask_to_set; | |
299 | } | |
300 | } | |
e5af323c | 301 | EXPORT_SYMBOL(__bitmap_set); |
c1a2a962 | 302 | |
e5af323c | 303 | void __bitmap_clear(unsigned long *map, unsigned int start, int len) |
c1a2a962 AM |
304 | { |
305 | unsigned long *p = map + BIT_WORD(start); | |
154f5e38 | 306 | const unsigned int size = start + len; |
c1a2a962 AM |
307 | int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); |
308 | unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); | |
309 | ||
154f5e38 | 310 | while (len - bits_to_clear >= 0) { |
c1a2a962 | 311 | *p &= ~mask_to_clear; |
154f5e38 | 312 | len -= bits_to_clear; |
c1a2a962 AM |
313 | bits_to_clear = BITS_PER_LONG; |
314 | mask_to_clear = ~0UL; | |
315 | p++; | |
316 | } | |
154f5e38 | 317 | if (len) { |
c1a2a962 AM |
318 | mask_to_clear &= BITMAP_LAST_WORD_MASK(size); |
319 | *p &= ~mask_to_clear; | |
320 | } | |
321 | } | |
e5af323c | 322 | EXPORT_SYMBOL(__bitmap_clear); |
c1a2a962 | 323 | |
5e19b013 MN |
324 | /** |
325 | * bitmap_find_next_zero_area_off - find a contiguous aligned zero area | |
c1a2a962 AM |
326 | * @map: The address to base the search on |
327 | * @size: The bitmap size in bits | |
328 | * @start: The bitnumber to start searching at | |
329 | * @nr: The number of zeroed bits we're looking for | |
330 | * @align_mask: Alignment mask for zero area | |
5e19b013 | 331 | * @align_offset: Alignment offset for zero area. |
c1a2a962 AM |
332 | * |
333 | * The @align_mask should be one less than a power of 2; the effect is that | |
5e19b013 MN |
334 | * the bit offset of all zero areas this function finds plus @align_offset |
335 | * is multiple of that power of 2. | |
c1a2a962 | 336 | */ |
5e19b013 MN |
337 | unsigned long bitmap_find_next_zero_area_off(unsigned long *map, |
338 | unsigned long size, | |
339 | unsigned long start, | |
340 | unsigned int nr, | |
341 | unsigned long align_mask, | |
342 | unsigned long align_offset) | |
c1a2a962 AM |
343 | { |
344 | unsigned long index, end, i; | |
345 | again: | |
346 | index = find_next_zero_bit(map, size, start); | |
347 | ||
348 | /* Align allocation */ | |
5e19b013 | 349 | index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; |
c1a2a962 AM |
350 | |
351 | end = index + nr; | |
352 | if (end > size) | |
353 | return end; | |
354 | i = find_next_bit(map, end, index); | |
355 | if (i < end) { | |
356 | start = i + 1; | |
357 | goto again; | |
358 | } | |
359 | return index; | |
360 | } | |
5e19b013 | 361 | EXPORT_SYMBOL(bitmap_find_next_zero_area_off); |
c1a2a962 | 362 | |
1da177e4 | 363 | /* |
6d49e352 | 364 | * Bitmap printing & parsing functions: first version by Nadia Yvette Chambers, |
1da177e4 LT |
365 | * second version by Paul Jackson, third by Joe Korty. |
366 | */ | |
367 | ||
368 | #define CHUNKSZ 32 | |
369 | #define nbits_to_hold_value(val) fls(val) | |
1da177e4 LT |
370 | #define BASEDEC 10 /* fancier cpuset lists input in decimal */ |
371 | ||
1da177e4 | 372 | /** |
01a3ee2b RC |
373 | * __bitmap_parse - convert an ASCII hex string into a bitmap. |
374 | * @buf: pointer to buffer containing string. | |
375 | * @buflen: buffer size in bytes. If string is smaller than this | |
1da177e4 | 376 | * then it must be terminated with a \0. |
01a3ee2b | 377 | * @is_user: location of buffer, 0 indicates kernel space |
1da177e4 LT |
378 | * @maskp: pointer to bitmap array that will contain result. |
379 | * @nmaskbits: size of bitmap, in bits. | |
380 | * | |
381 | * Commas group hex digits into chunks. Each chunk defines exactly 32 | |
382 | * bits of the resultant bitmask. No chunk may specify a value larger | |
6e1907ff RD |
383 | * than 32 bits (%-EOVERFLOW), and if a chunk specifies a smaller value |
384 | * then leading 0-bits are prepended. %-EINVAL is returned for illegal | |
1da177e4 LT |
385 | * characters and for grouping errors such as "1,,5", ",44", "," and "". |
386 | * Leading and trailing whitespace accepted, but not embedded whitespace. | |
387 | */ | |
01a3ee2b RC |
388 | int __bitmap_parse(const char *buf, unsigned int buflen, |
389 | int is_user, unsigned long *maskp, | |
390 | int nmaskbits) | |
1da177e4 LT |
391 | { |
392 | int c, old_c, totaldigits, ndigits, nchunks, nbits; | |
393 | u32 chunk; | |
b9c321fd | 394 | const char __user __force *ubuf = (const char __user __force *)buf; |
1da177e4 LT |
395 | |
396 | bitmap_zero(maskp, nmaskbits); | |
397 | ||
398 | nchunks = nbits = totaldigits = c = 0; | |
399 | do { | |
d21c3d4d PX |
400 | chunk = 0; |
401 | ndigits = totaldigits; | |
1da177e4 LT |
402 | |
403 | /* Get the next chunk of the bitmap */ | |
01a3ee2b | 404 | while (buflen) { |
1da177e4 | 405 | old_c = c; |
01a3ee2b RC |
406 | if (is_user) { |
407 | if (__get_user(c, ubuf++)) | |
408 | return -EFAULT; | |
409 | } | |
410 | else | |
411 | c = *buf++; | |
412 | buflen--; | |
1da177e4 LT |
413 | if (isspace(c)) |
414 | continue; | |
415 | ||
416 | /* | |
417 | * If the last character was a space and the current | |
418 | * character isn't '\0', we've got embedded whitespace. | |
419 | * This is a no-no, so throw an error. | |
420 | */ | |
421 | if (totaldigits && c && isspace(old_c)) | |
422 | return -EINVAL; | |
423 | ||
424 | /* A '\0' or a ',' signal the end of the chunk */ | |
425 | if (c == '\0' || c == ',') | |
426 | break; | |
427 | ||
428 | if (!isxdigit(c)) | |
429 | return -EINVAL; | |
430 | ||
431 | /* | |
432 | * Make sure there are at least 4 free bits in 'chunk'. | |
433 | * If not, this hexdigit will overflow 'chunk', so | |
434 | * throw an error. | |
435 | */ | |
436 | if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1)) | |
437 | return -EOVERFLOW; | |
438 | ||
66f1991b | 439 | chunk = (chunk << 4) | hex_to_bin(c); |
d21c3d4d | 440 | totaldigits++; |
1da177e4 | 441 | } |
d21c3d4d | 442 | if (ndigits == totaldigits) |
1da177e4 LT |
443 | return -EINVAL; |
444 | if (nchunks == 0 && chunk == 0) | |
445 | continue; | |
446 | ||
447 | __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits); | |
448 | *maskp |= chunk; | |
449 | nchunks++; | |
450 | nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ; | |
451 | if (nbits > nmaskbits) | |
452 | return -EOVERFLOW; | |
01a3ee2b | 453 | } while (buflen && c == ','); |
1da177e4 LT |
454 | |
455 | return 0; | |
456 | } | |
01a3ee2b RC |
457 | EXPORT_SYMBOL(__bitmap_parse); |
458 | ||
459 | /** | |
9a86e2ba | 460 | * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap |
01a3ee2b RC |
461 | * |
462 | * @ubuf: pointer to user buffer containing string. | |
463 | * @ulen: buffer size in bytes. If string is smaller than this | |
464 | * then it must be terminated with a \0. | |
465 | * @maskp: pointer to bitmap array that will contain result. | |
466 | * @nmaskbits: size of bitmap, in bits. | |
467 | * | |
468 | * Wrapper for __bitmap_parse(), providing it with user buffer. | |
469 | * | |
470 | * We cannot have this as an inline function in bitmap.h because it needs | |
471 | * linux/uaccess.h to get the access_ok() declaration and this causes | |
472 | * cyclic dependencies. | |
473 | */ | |
474 | int bitmap_parse_user(const char __user *ubuf, | |
475 | unsigned int ulen, unsigned long *maskp, | |
476 | int nmaskbits) | |
477 | { | |
96d4f267 | 478 | if (!access_ok(ubuf, ulen)) |
01a3ee2b | 479 | return -EFAULT; |
b9c321fd HS |
480 | return __bitmap_parse((const char __force *)ubuf, |
481 | ulen, 1, maskp, nmaskbits); | |
482 | ||
01a3ee2b RC |
483 | } |
484 | EXPORT_SYMBOL(bitmap_parse_user); | |
1da177e4 | 485 | |
5aaba363 SH |
486 | /** |
487 | * bitmap_print_to_pagebuf - convert bitmap to list or hex format ASCII string | |
488 | * @list: indicates whether the bitmap must be list | |
489 | * @buf: page aligned buffer into which string is placed | |
490 | * @maskp: pointer to bitmap to convert | |
491 | * @nmaskbits: size of bitmap, in bits | |
492 | * | |
493 | * Output format is a comma-separated list of decimal numbers and | |
494 | * ranges if list is specified or hex digits grouped into comma-separated | |
495 | * sets of 8 digits/set. Returns the number of characters written to buf. | |
9cf79d11 | 496 | * |
ce1091d4 RV |
497 | * It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned |
498 | * area and that sufficient storage remains at @buf to accommodate the | |
499 | * bitmap_print_to_pagebuf() output. Returns the number of characters | |
500 | * actually printed to @buf, excluding terminating '\0'. | |
5aaba363 SH |
501 | */ |
502 | int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp, | |
503 | int nmaskbits) | |
504 | { | |
ce1091d4 | 505 | ptrdiff_t len = PAGE_SIZE - offset_in_page(buf); |
5aaba363 | 506 | |
8ec3d768 RV |
507 | return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) : |
508 | scnprintf(buf, len, "%*pb\n", nmaskbits, maskp); | |
5aaba363 SH |
509 | } |
510 | EXPORT_SYMBOL(bitmap_print_to_pagebuf); | |
511 | ||
e371c481 YN |
512 | /* |
513 | * Region 9-38:4/10 describes the following bitmap structure: | |
514 | * 0 9 12 18 38 | |
515 | * .........****......****......****...... | |
516 | * ^ ^ ^ ^ | |
517 | * start off group_len end | |
518 | */ | |
519 | struct region { | |
520 | unsigned int start; | |
521 | unsigned int off; | |
522 | unsigned int group_len; | |
523 | unsigned int end; | |
524 | }; | |
525 | ||
526 | static int bitmap_set_region(const struct region *r, | |
527 | unsigned long *bitmap, int nbits) | |
528 | { | |
529 | unsigned int start; | |
530 | ||
531 | if (r->end >= nbits) | |
532 | return -ERANGE; | |
533 | ||
534 | for (start = r->start; start <= r->end; start += r->group_len) | |
535 | bitmap_set(bitmap, start, min(r->end - start + 1, r->off)); | |
536 | ||
537 | return 0; | |
538 | } | |
539 | ||
540 | static int bitmap_check_region(const struct region *r) | |
541 | { | |
542 | if (r->start > r->end || r->group_len == 0 || r->off > r->group_len) | |
543 | return -EINVAL; | |
544 | ||
545 | return 0; | |
546 | } | |
547 | ||
548 | static const char *bitmap_getnum(const char *str, unsigned int *num) | |
549 | { | |
550 | unsigned long long n; | |
551 | unsigned int len; | |
552 | ||
553 | len = _parse_integer(str, 10, &n); | |
554 | if (!len) | |
555 | return ERR_PTR(-EINVAL); | |
556 | if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n) | |
557 | return ERR_PTR(-EOVERFLOW); | |
558 | ||
559 | *num = n; | |
560 | return str + len; | |
561 | } | |
562 | ||
563 | static inline bool end_of_str(char c) | |
564 | { | |
565 | return c == '\0' || c == '\n'; | |
566 | } | |
567 | ||
568 | static inline bool __end_of_region(char c) | |
569 | { | |
570 | return isspace(c) || c == ','; | |
571 | } | |
572 | ||
573 | static inline bool end_of_region(char c) | |
574 | { | |
575 | return __end_of_region(c) || end_of_str(c); | |
576 | } | |
577 | ||
578 | /* | |
579 | * The format allows commas and whitespases at the beginning | |
580 | * of the region. | |
581 | */ | |
582 | static const char *bitmap_find_region(const char *str) | |
583 | { | |
584 | while (__end_of_region(*str)) | |
585 | str++; | |
586 | ||
587 | return end_of_str(*str) ? NULL : str; | |
588 | } | |
589 | ||
590 | static const char *bitmap_parse_region(const char *str, struct region *r) | |
591 | { | |
592 | str = bitmap_getnum(str, &r->start); | |
593 | if (IS_ERR(str)) | |
594 | return str; | |
595 | ||
596 | if (end_of_region(*str)) | |
597 | goto no_end; | |
598 | ||
599 | if (*str != '-') | |
600 | return ERR_PTR(-EINVAL); | |
601 | ||
602 | str = bitmap_getnum(str + 1, &r->end); | |
603 | if (IS_ERR(str)) | |
604 | return str; | |
605 | ||
606 | if (end_of_region(*str)) | |
607 | goto no_pattern; | |
608 | ||
609 | if (*str != ':') | |
610 | return ERR_PTR(-EINVAL); | |
611 | ||
612 | str = bitmap_getnum(str + 1, &r->off); | |
613 | if (IS_ERR(str)) | |
614 | return str; | |
615 | ||
616 | if (*str != '/') | |
617 | return ERR_PTR(-EINVAL); | |
618 | ||
619 | return bitmap_getnum(str + 1, &r->group_len); | |
620 | ||
621 | no_end: | |
622 | r->end = r->start; | |
623 | no_pattern: | |
624 | r->off = r->end + 1; | |
625 | r->group_len = r->end + 1; | |
626 | ||
627 | return end_of_str(*str) ? NULL : str; | |
628 | } | |
629 | ||
1da177e4 | 630 | /** |
e371c481 YN |
631 | * bitmap_parselist - convert list format ASCII string to bitmap |
632 | * @buf: read user string from this buffer; must be terminated | |
633 | * with a \0 or \n. | |
6e1907ff | 634 | * @maskp: write resulting mask here |
1da177e4 LT |
635 | * @nmaskbits: number of bits in mask to be written |
636 | * | |
637 | * Input format is a comma-separated list of decimal numbers and | |
638 | * ranges. Consecutively set bits are shown as two hyphen-separated | |
639 | * decimal numbers, the smallest and largest bit numbers set in | |
640 | * the range. | |
2d13e6ca NC |
641 | * Optionally each range can be postfixed to denote that only parts of it |
642 | * should be set. The range will divided to groups of specific size. | |
643 | * From each group will be used only defined amount of bits. | |
644 | * Syntax: range:used_size/group_size | |
645 | * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 | |
1da177e4 | 646 | * |
40bf19a8 MCC |
647 | * Returns: 0 on success, -errno on invalid input strings. Error values: |
648 | * | |
e371c481 | 649 | * - ``-EINVAL``: wrong region format |
40bf19a8 MCC |
650 | * - ``-EINVAL``: invalid character in string |
651 | * - ``-ERANGE``: bit number specified too large for mask | |
e371c481 | 652 | * - ``-EOVERFLOW``: integer overflow in the input parameters |
1da177e4 | 653 | */ |
e371c481 | 654 | int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) |
1da177e4 | 655 | { |
e371c481 YN |
656 | struct region r; |
657 | long ret; | |
1da177e4 LT |
658 | |
659 | bitmap_zero(maskp, nmaskbits); | |
4b060420 | 660 | |
e371c481 YN |
661 | while (buf) { |
662 | buf = bitmap_find_region(buf); | |
663 | if (buf == NULL) | |
664 | return 0; | |
2d13e6ca | 665 | |
e371c481 YN |
666 | buf = bitmap_parse_region(buf, &r); |
667 | if (IS_ERR(buf)) | |
668 | return PTR_ERR(buf); | |
2d13e6ca | 669 | |
e371c481 YN |
670 | ret = bitmap_check_region(&r); |
671 | if (ret) | |
672 | return ret; | |
4b060420 | 673 | |
e371c481 YN |
674 | ret = bitmap_set_region(&r, maskp, nmaskbits); |
675 | if (ret) | |
676 | return ret; | |
677 | } | |
4b060420 | 678 | |
1da177e4 LT |
679 | return 0; |
680 | } | |
681 | EXPORT_SYMBOL(bitmap_parselist); | |
682 | ||
4b060420 MT |
683 | |
684 | /** | |
685 | * bitmap_parselist_user() | |
686 | * | |
687 | * @ubuf: pointer to user buffer containing string. | |
688 | * @ulen: buffer size in bytes. If string is smaller than this | |
689 | * then it must be terminated with a \0. | |
690 | * @maskp: pointer to bitmap array that will contain result. | |
691 | * @nmaskbits: size of bitmap, in bits. | |
692 | * | |
693 | * Wrapper for bitmap_parselist(), providing it with user buffer. | |
4b060420 MT |
694 | */ |
695 | int bitmap_parselist_user(const char __user *ubuf, | |
696 | unsigned int ulen, unsigned long *maskp, | |
697 | int nmaskbits) | |
698 | { | |
281327c9 YN |
699 | char *buf; |
700 | int ret; | |
701 | ||
702 | buf = memdup_user_nul(ubuf, ulen); | |
703 | if (IS_ERR(buf)) | |
704 | return PTR_ERR(buf); | |
705 | ||
706 | ret = bitmap_parselist(buf, maskp, nmaskbits); | |
707 | ||
708 | kfree(buf); | |
709 | return ret; | |
4b060420 MT |
710 | } |
711 | EXPORT_SYMBOL(bitmap_parselist_user); | |
712 | ||
713 | ||
cdc90a18 | 714 | #ifdef CONFIG_NUMA |
72fd4a35 | 715 | /** |
9a86e2ba | 716 | * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap |
fb5eeeee | 717 | * @buf: pointer to a bitmap |
df1d80a9 RV |
718 | * @pos: a bit position in @buf (0 <= @pos < @nbits) |
719 | * @nbits: number of valid bit positions in @buf | |
fb5eeeee | 720 | * |
df1d80a9 | 721 | * Map the bit at position @pos in @buf (of length @nbits) to the |
fb5eeeee | 722 | * ordinal of which set bit it is. If it is not set or if @pos |
96b7f341 | 723 | * is not a valid bit position, map to -1. |
fb5eeeee PJ |
724 | * |
725 | * If for example, just bits 4 through 7 are set in @buf, then @pos | |
726 | * values 4 through 7 will get mapped to 0 through 3, respectively, | |
a8551748 | 727 | * and other @pos values will get mapped to -1. When @pos value 7 |
fb5eeeee PJ |
728 | * gets mapped to (returns) @ord value 3 in this example, that means |
729 | * that bit 7 is the 3rd (starting with 0th) set bit in @buf. | |
730 | * | |
731 | * The bit positions 0 through @bits are valid positions in @buf. | |
732 | */ | |
df1d80a9 | 733 | static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) |
fb5eeeee | 734 | { |
df1d80a9 | 735 | if (pos >= nbits || !test_bit(pos, buf)) |
96b7f341 | 736 | return -1; |
fb5eeeee | 737 | |
df1d80a9 | 738 | return __bitmap_weight(buf, pos); |
fb5eeeee PJ |
739 | } |
740 | ||
741 | /** | |
9a86e2ba | 742 | * bitmap_ord_to_pos - find position of n-th set bit in bitmap |
fb5eeeee PJ |
743 | * @buf: pointer to bitmap |
744 | * @ord: ordinal bit position (n-th set bit, n >= 0) | |
f6a1f5db | 745 | * @nbits: number of valid bit positions in @buf |
fb5eeeee PJ |
746 | * |
747 | * Map the ordinal offset of bit @ord in @buf to its position in @buf. | |
f6a1f5db RV |
748 | * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord |
749 | * >= weight(buf), returns @nbits. | |
fb5eeeee PJ |
750 | * |
751 | * If for example, just bits 4 through 7 are set in @buf, then @ord | |
752 | * values 0 through 3 will get mapped to 4 through 7, respectively, | |
f6a1f5db | 753 | * and all other @ord values returns @nbits. When @ord value 3 |
fb5eeeee PJ |
754 | * gets mapped to (returns) @pos value 7 in this example, that means |
755 | * that the 3rd set bit (starting with 0th) is at position 7 in @buf. | |
756 | * | |
f6a1f5db | 757 | * The bit positions 0 through @nbits-1 are valid positions in @buf. |
fb5eeeee | 758 | */ |
f6a1f5db | 759 | unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits) |
fb5eeeee | 760 | { |
f6a1f5db | 761 | unsigned int pos; |
fb5eeeee | 762 | |
f6a1f5db RV |
763 | for (pos = find_first_bit(buf, nbits); |
764 | pos < nbits && ord; | |
765 | pos = find_next_bit(buf, nbits, pos + 1)) | |
766 | ord--; | |
fb5eeeee PJ |
767 | |
768 | return pos; | |
769 | } | |
770 | ||
771 | /** | |
772 | * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap | |
fb5eeeee | 773 | * @dst: remapped result |
96b7f341 | 774 | * @src: subset to be remapped |
fb5eeeee PJ |
775 | * @old: defines domain of map |
776 | * @new: defines range of map | |
9814ec13 | 777 | * @nbits: number of bits in each of these bitmaps |
fb5eeeee PJ |
778 | * |
779 | * Let @old and @new define a mapping of bit positions, such that | |
780 | * whatever position is held by the n-th set bit in @old is mapped | |
781 | * to the n-th set bit in @new. In the more general case, allowing | |
782 | * for the possibility that the weight 'w' of @new is less than the | |
783 | * weight of @old, map the position of the n-th set bit in @old to | |
784 | * the position of the m-th set bit in @new, where m == n % w. | |
785 | * | |
96b7f341 PJ |
786 | * If either of the @old and @new bitmaps are empty, or if @src and |
787 | * @dst point to the same location, then this routine copies @src | |
788 | * to @dst. | |
fb5eeeee | 789 | * |
96b7f341 PJ |
790 | * The positions of unset bits in @old are mapped to themselves |
791 | * (the identify map). | |
fb5eeeee PJ |
792 | * |
793 | * Apply the above specified mapping to @src, placing the result in | |
794 | * @dst, clearing any bits previously set in @dst. | |
795 | * | |
fb5eeeee PJ |
796 | * For example, lets say that @old has bits 4 through 7 set, and |
797 | * @new has bits 12 through 15 set. This defines the mapping of bit | |
798 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other | |
96b7f341 PJ |
799 | * bit positions unchanged. So if say @src comes into this routine |
800 | * with bits 1, 5 and 7 set, then @dst should leave with bits 1, | |
801 | * 13 and 15 set. | |
fb5eeeee PJ |
802 | */ |
803 | void bitmap_remap(unsigned long *dst, const unsigned long *src, | |
804 | const unsigned long *old, const unsigned long *new, | |
9814ec13 | 805 | unsigned int nbits) |
fb5eeeee | 806 | { |
9814ec13 | 807 | unsigned int oldbit, w; |
fb5eeeee | 808 | |
fb5eeeee PJ |
809 | if (dst == src) /* following doesn't handle inplace remaps */ |
810 | return; | |
9814ec13 | 811 | bitmap_zero(dst, nbits); |
96b7f341 | 812 | |
9814ec13 RV |
813 | w = bitmap_weight(new, nbits); |
814 | for_each_set_bit(oldbit, src, nbits) { | |
815 | int n = bitmap_pos_to_ord(old, oldbit, nbits); | |
08564fb7 | 816 | |
96b7f341 PJ |
817 | if (n < 0 || w == 0) |
818 | set_bit(oldbit, dst); /* identity map */ | |
819 | else | |
9814ec13 | 820 | set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst); |
fb5eeeee PJ |
821 | } |
822 | } | |
fb5eeeee PJ |
823 | |
824 | /** | |
825 | * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit | |
6e1907ff RD |
826 | * @oldbit: bit position to be mapped |
827 | * @old: defines domain of map | |
828 | * @new: defines range of map | |
829 | * @bits: number of bits in each of these bitmaps | |
fb5eeeee PJ |
830 | * |
831 | * Let @old and @new define a mapping of bit positions, such that | |
832 | * whatever position is held by the n-th set bit in @old is mapped | |
833 | * to the n-th set bit in @new. In the more general case, allowing | |
834 | * for the possibility that the weight 'w' of @new is less than the | |
835 | * weight of @old, map the position of the n-th set bit in @old to | |
836 | * the position of the m-th set bit in @new, where m == n % w. | |
837 | * | |
96b7f341 PJ |
838 | * The positions of unset bits in @old are mapped to themselves |
839 | * (the identify map). | |
fb5eeeee PJ |
840 | * |
841 | * Apply the above specified mapping to bit position @oldbit, returning | |
842 | * the new bit position. | |
843 | * | |
844 | * For example, lets say that @old has bits 4 through 7 set, and | |
845 | * @new has bits 12 through 15 set. This defines the mapping of bit | |
846 | * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other | |
96b7f341 PJ |
847 | * bit positions unchanged. So if say @oldbit is 5, then this routine |
848 | * returns 13. | |
fb5eeeee PJ |
849 | */ |
850 | int bitmap_bitremap(int oldbit, const unsigned long *old, | |
851 | const unsigned long *new, int bits) | |
852 | { | |
96b7f341 PJ |
853 | int w = bitmap_weight(new, bits); |
854 | int n = bitmap_pos_to_ord(old, oldbit, bits); | |
855 | if (n < 0 || w == 0) | |
856 | return oldbit; | |
857 | else | |
858 | return bitmap_ord_to_pos(new, n % w, bits); | |
fb5eeeee | 859 | } |
fb5eeeee | 860 | |
7ea931c9 PJ |
861 | /** |
862 | * bitmap_onto - translate one bitmap relative to another | |
863 | * @dst: resulting translated bitmap | |
864 | * @orig: original untranslated bitmap | |
865 | * @relmap: bitmap relative to which translated | |
866 | * @bits: number of bits in each of these bitmaps | |
867 | * | |
868 | * Set the n-th bit of @dst iff there exists some m such that the | |
869 | * n-th bit of @relmap is set, the m-th bit of @orig is set, and | |
870 | * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. | |
871 | * (If you understood the previous sentence the first time your | |
872 | * read it, you're overqualified for your current job.) | |
873 | * | |
874 | * In other words, @orig is mapped onto (surjectively) @dst, | |
da3dae54 | 875 | * using the map { <n, m> | the n-th bit of @relmap is the |
7ea931c9 PJ |
876 | * m-th set bit of @relmap }. |
877 | * | |
878 | * Any set bits in @orig above bit number W, where W is the | |
879 | * weight of (number of set bits in) @relmap are mapped nowhere. | |
880 | * In particular, if for all bits m set in @orig, m >= W, then | |
881 | * @dst will end up empty. In situations where the possibility | |
882 | * of such an empty result is not desired, one way to avoid it is | |
883 | * to use the bitmap_fold() operator, below, to first fold the | |
884 | * @orig bitmap over itself so that all its set bits x are in the | |
885 | * range 0 <= x < W. The bitmap_fold() operator does this by | |
886 | * setting the bit (m % W) in @dst, for each bit (m) set in @orig. | |
887 | * | |
888 | * Example [1] for bitmap_onto(): | |
889 | * Let's say @relmap has bits 30-39 set, and @orig has bits | |
890 | * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, | |
891 | * @dst will have bits 31, 33, 35, 37 and 39 set. | |
892 | * | |
893 | * When bit 0 is set in @orig, it means turn on the bit in | |
894 | * @dst corresponding to whatever is the first bit (if any) | |
895 | * that is turned on in @relmap. Since bit 0 was off in the | |
896 | * above example, we leave off that bit (bit 30) in @dst. | |
897 | * | |
898 | * When bit 1 is set in @orig (as in the above example), it | |
899 | * means turn on the bit in @dst corresponding to whatever | |
900 | * is the second bit that is turned on in @relmap. The second | |
901 | * bit in @relmap that was turned on in the above example was | |
902 | * bit 31, so we turned on bit 31 in @dst. | |
903 | * | |
904 | * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, | |
905 | * because they were the 4th, 6th, 8th and 10th set bits | |
906 | * set in @relmap, and the 4th, 6th, 8th and 10th bits of | |
907 | * @orig (i.e. bits 3, 5, 7 and 9) were also set. | |
908 | * | |
909 | * When bit 11 is set in @orig, it means turn on the bit in | |
25985edc | 910 | * @dst corresponding to whatever is the twelfth bit that is |
7ea931c9 PJ |
911 | * turned on in @relmap. In the above example, there were |
912 | * only ten bits turned on in @relmap (30..39), so that bit | |
913 | * 11 was set in @orig had no affect on @dst. | |
914 | * | |
915 | * Example [2] for bitmap_fold() + bitmap_onto(): | |
40bf19a8 MCC |
916 | * Let's say @relmap has these ten bits set:: |
917 | * | |
7ea931c9 | 918 | * 40 41 42 43 45 48 53 61 74 95 |
40bf19a8 | 919 | * |
7ea931c9 PJ |
920 | * (for the curious, that's 40 plus the first ten terms of the |
921 | * Fibonacci sequence.) | |
922 | * | |
923 | * Further lets say we use the following code, invoking | |
924 | * bitmap_fold() then bitmap_onto, as suggested above to | |
40bf19a8 | 925 | * avoid the possibility of an empty @dst result:: |
7ea931c9 PJ |
926 | * |
927 | * unsigned long *tmp; // a temporary bitmap's bits | |
928 | * | |
929 | * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); | |
930 | * bitmap_onto(dst, tmp, relmap, bits); | |
931 | * | |
932 | * Then this table shows what various values of @dst would be, for | |
933 | * various @orig's. I list the zero-based positions of each set bit. | |
934 | * The tmp column shows the intermediate result, as computed by | |
935 | * using bitmap_fold() to fold the @orig bitmap modulo ten | |
40bf19a8 | 936 | * (the weight of @relmap): |
7ea931c9 | 937 | * |
40bf19a8 | 938 | * =============== ============== ================= |
7ea931c9 PJ |
939 | * @orig tmp @dst |
940 | * 0 0 40 | |
941 | * 1 1 41 | |
942 | * 9 9 95 | |
40bf19a8 | 943 | * 10 0 40 [#f1]_ |
7ea931c9 PJ |
944 | * 1 3 5 7 1 3 5 7 41 43 48 61 |
945 | * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 | |
946 | * 0 9 18 27 0 9 8 7 40 61 74 95 | |
947 | * 0 10 20 30 0 40 | |
948 | * 0 11 22 33 0 1 2 3 40 41 42 43 | |
949 | * 0 12 24 36 0 2 4 6 40 42 45 53 | |
40bf19a8 MCC |
950 | * 78 102 211 1 2 8 41 42 74 [#f1]_ |
951 | * =============== ============== ================= | |
952 | * | |
953 | * .. [#f1] | |
7ea931c9 | 954 | * |
40bf19a8 | 955 | * For these marked lines, if we hadn't first done bitmap_fold() |
7ea931c9 PJ |
956 | * into tmp, then the @dst result would have been empty. |
957 | * | |
958 | * If either of @orig or @relmap is empty (no set bits), then @dst | |
959 | * will be returned empty. | |
960 | * | |
961 | * If (as explained above) the only set bits in @orig are in positions | |
962 | * m where m >= W, (where W is the weight of @relmap) then @dst will | |
963 | * once again be returned empty. | |
964 | * | |
965 | * All bits in @dst not set by the above rule are cleared. | |
966 | */ | |
967 | void bitmap_onto(unsigned long *dst, const unsigned long *orig, | |
eb569883 | 968 | const unsigned long *relmap, unsigned int bits) |
7ea931c9 | 969 | { |
eb569883 | 970 | unsigned int n, m; /* same meaning as in above comment */ |
7ea931c9 PJ |
971 | |
972 | if (dst == orig) /* following doesn't handle inplace mappings */ | |
973 | return; | |
974 | bitmap_zero(dst, bits); | |
975 | ||
976 | /* | |
977 | * The following code is a more efficient, but less | |
978 | * obvious, equivalent to the loop: | |
979 | * for (m = 0; m < bitmap_weight(relmap, bits); m++) { | |
980 | * n = bitmap_ord_to_pos(orig, m, bits); | |
981 | * if (test_bit(m, orig)) | |
982 | * set_bit(n, dst); | |
983 | * } | |
984 | */ | |
985 | ||
986 | m = 0; | |
08564fb7 | 987 | for_each_set_bit(n, relmap, bits) { |
7ea931c9 PJ |
988 | /* m == bitmap_pos_to_ord(relmap, n, bits) */ |
989 | if (test_bit(m, orig)) | |
990 | set_bit(n, dst); | |
991 | m++; | |
992 | } | |
993 | } | |
7ea931c9 PJ |
994 | |
995 | /** | |
996 | * bitmap_fold - fold larger bitmap into smaller, modulo specified size | |
997 | * @dst: resulting smaller bitmap | |
998 | * @orig: original larger bitmap | |
999 | * @sz: specified size | |
b26ad583 | 1000 | * @nbits: number of bits in each of these bitmaps |
7ea931c9 PJ |
1001 | * |
1002 | * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. | |
1003 | * Clear all other bits in @dst. See further the comment and | |
1004 | * Example [2] for bitmap_onto() for why and how to use this. | |
1005 | */ | |
1006 | void bitmap_fold(unsigned long *dst, const unsigned long *orig, | |
b26ad583 | 1007 | unsigned int sz, unsigned int nbits) |
7ea931c9 | 1008 | { |
b26ad583 | 1009 | unsigned int oldbit; |
7ea931c9 PJ |
1010 | |
1011 | if (dst == orig) /* following doesn't handle inplace mappings */ | |
1012 | return; | |
b26ad583 | 1013 | bitmap_zero(dst, nbits); |
7ea931c9 | 1014 | |
b26ad583 | 1015 | for_each_set_bit(oldbit, orig, nbits) |
7ea931c9 PJ |
1016 | set_bit(oldbit % sz, dst); |
1017 | } | |
cdc90a18 | 1018 | #endif /* CONFIG_NUMA */ |
7ea931c9 | 1019 | |
3cf64b93 PJ |
1020 | /* |
1021 | * Common code for bitmap_*_region() routines. | |
1022 | * bitmap: array of unsigned longs corresponding to the bitmap | |
1023 | * pos: the beginning of the region | |
1024 | * order: region size (log base 2 of number of bits) | |
1025 | * reg_op: operation(s) to perform on that region of bitmap | |
1da177e4 | 1026 | * |
3cf64b93 PJ |
1027 | * Can set, verify and/or release a region of bits in a bitmap, |
1028 | * depending on which combination of REG_OP_* flag bits is set. | |
1da177e4 | 1029 | * |
3cf64b93 PJ |
1030 | * A region of a bitmap is a sequence of bits in the bitmap, of |
1031 | * some size '1 << order' (a power of two), aligned to that same | |
1032 | * '1 << order' power of two. | |
1033 | * | |
1034 | * Returns 1 if REG_OP_ISFREE succeeds (region is all zero bits). | |
1035 | * Returns 0 in all other cases and reg_ops. | |
1da177e4 | 1036 | */ |
3cf64b93 PJ |
1037 | |
1038 | enum { | |
1039 | REG_OP_ISFREE, /* true if region is all zero bits */ | |
1040 | REG_OP_ALLOC, /* set all bits in region */ | |
1041 | REG_OP_RELEASE, /* clear all bits in region */ | |
1042 | }; | |
1043 | ||
9279d328 | 1044 | static int __reg_op(unsigned long *bitmap, unsigned int pos, int order, int reg_op) |
1da177e4 | 1045 | { |
3cf64b93 PJ |
1046 | int nbits_reg; /* number of bits in region */ |
1047 | int index; /* index first long of region in bitmap */ | |
1048 | int offset; /* bit offset region in bitmap[index] */ | |
1049 | int nlongs_reg; /* num longs spanned by region in bitmap */ | |
74373c6a | 1050 | int nbitsinlong; /* num bits of region in each spanned long */ |
3cf64b93 | 1051 | unsigned long mask; /* bitmask for one long of region */ |
74373c6a | 1052 | int i; /* scans bitmap by longs */ |
3cf64b93 | 1053 | int ret = 0; /* return value */ |
74373c6a | 1054 | |
3cf64b93 PJ |
1055 | /* |
1056 | * Either nlongs_reg == 1 (for small orders that fit in one long) | |
1057 | * or (offset == 0 && mask == ~0UL) (for larger multiword orders.) | |
1058 | */ | |
1059 | nbits_reg = 1 << order; | |
1060 | index = pos / BITS_PER_LONG; | |
1061 | offset = pos - (index * BITS_PER_LONG); | |
1062 | nlongs_reg = BITS_TO_LONGS(nbits_reg); | |
1063 | nbitsinlong = min(nbits_reg, BITS_PER_LONG); | |
1da177e4 | 1064 | |
3cf64b93 PJ |
1065 | /* |
1066 | * Can't do "mask = (1UL << nbitsinlong) - 1", as that | |
1067 | * overflows if nbitsinlong == BITS_PER_LONG. | |
1068 | */ | |
74373c6a | 1069 | mask = (1UL << (nbitsinlong - 1)); |
1da177e4 | 1070 | mask += mask - 1; |
3cf64b93 | 1071 | mask <<= offset; |
1da177e4 | 1072 | |
3cf64b93 PJ |
1073 | switch (reg_op) { |
1074 | case REG_OP_ISFREE: | |
1075 | for (i = 0; i < nlongs_reg; i++) { | |
1076 | if (bitmap[index + i] & mask) | |
1077 | goto done; | |
1078 | } | |
1079 | ret = 1; /* all bits in region free (zero) */ | |
1080 | break; | |
1081 | ||
1082 | case REG_OP_ALLOC: | |
1083 | for (i = 0; i < nlongs_reg; i++) | |
1084 | bitmap[index + i] |= mask; | |
1085 | break; | |
1086 | ||
1087 | case REG_OP_RELEASE: | |
1088 | for (i = 0; i < nlongs_reg; i++) | |
1089 | bitmap[index + i] &= ~mask; | |
1090 | break; | |
1da177e4 | 1091 | } |
3cf64b93 PJ |
1092 | done: |
1093 | return ret; | |
1094 | } | |
1095 | ||
1096 | /** | |
1097 | * bitmap_find_free_region - find a contiguous aligned mem region | |
1098 | * @bitmap: array of unsigned longs corresponding to the bitmap | |
1099 | * @bits: number of bits in the bitmap | |
1100 | * @order: region size (log base 2 of number of bits) to find | |
1101 | * | |
1102 | * Find a region of free (zero) bits in a @bitmap of @bits bits and | |
1103 | * allocate them (set them to one). Only consider regions of length | |
1104 | * a power (@order) of two, aligned to that power of two, which | |
1105 | * makes the search algorithm much faster. | |
1106 | * | |
1107 | * Return the bit offset in bitmap of the allocated region, | |
1108 | * or -errno on failure. | |
1109 | */ | |
9279d328 | 1110 | int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) |
3cf64b93 | 1111 | { |
9279d328 | 1112 | unsigned int pos, end; /* scans bitmap by regions of size order */ |
aa8e4fc6 | 1113 | |
9279d328 | 1114 | for (pos = 0 ; (end = pos + (1U << order)) <= bits; pos = end) { |
aa8e4fc6 LT |
1115 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1116 | continue; | |
1117 | __reg_op(bitmap, pos, order, REG_OP_ALLOC); | |
1118 | return pos; | |
1119 | } | |
1120 | return -ENOMEM; | |
1da177e4 LT |
1121 | } |
1122 | EXPORT_SYMBOL(bitmap_find_free_region); | |
1123 | ||
1124 | /** | |
87e24802 | 1125 | * bitmap_release_region - release allocated bitmap region |
3cf64b93 PJ |
1126 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1127 | * @pos: beginning of bit region to release | |
1128 | * @order: region size (log base 2 of number of bits) to release | |
1da177e4 | 1129 | * |
72fd4a35 | 1130 | * This is the complement to __bitmap_find_free_region() and releases |
1da177e4 | 1131 | * the found region (by clearing it in the bitmap). |
3cf64b93 PJ |
1132 | * |
1133 | * No return value. | |
1da177e4 | 1134 | */ |
9279d328 | 1135 | void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4 | 1136 | { |
3cf64b93 | 1137 | __reg_op(bitmap, pos, order, REG_OP_RELEASE); |
1da177e4 LT |
1138 | } |
1139 | EXPORT_SYMBOL(bitmap_release_region); | |
1140 | ||
87e24802 PJ |
1141 | /** |
1142 | * bitmap_allocate_region - allocate bitmap region | |
3cf64b93 PJ |
1143 | * @bitmap: array of unsigned longs corresponding to the bitmap |
1144 | * @pos: beginning of bit region to allocate | |
1145 | * @order: region size (log base 2 of number of bits) to allocate | |
87e24802 PJ |
1146 | * |
1147 | * Allocate (set bits in) a specified region of a bitmap. | |
3cf64b93 | 1148 | * |
6e1907ff | 1149 | * Return 0 on success, or %-EBUSY if specified region wasn't |
87e24802 PJ |
1150 | * free (not all bits were zero). |
1151 | */ | |
9279d328 | 1152 | int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) |
1da177e4 | 1153 | { |
3cf64b93 PJ |
1154 | if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE)) |
1155 | return -EBUSY; | |
2ac521d3 | 1156 | return __reg_op(bitmap, pos, order, REG_OP_ALLOC); |
1da177e4 LT |
1157 | } |
1158 | EXPORT_SYMBOL(bitmap_allocate_region); | |
ccbe329b DV |
1159 | |
1160 | /** | |
1161 | * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. | |
1162 | * @dst: destination buffer | |
1163 | * @src: bitmap to copy | |
1164 | * @nbits: number of bits in the bitmap | |
1165 | * | |
1166 | * Require nbits % BITS_PER_LONG == 0. | |
1167 | */ | |
e8f24278 | 1168 | #ifdef __BIG_ENDIAN |
9b6c2d2e | 1169 | void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) |
ccbe329b | 1170 | { |
9b6c2d2e | 1171 | unsigned int i; |
ccbe329b DV |
1172 | |
1173 | for (i = 0; i < nbits/BITS_PER_LONG; i++) { | |
1174 | if (BITS_PER_LONG == 64) | |
9b6c2d2e | 1175 | dst[i] = cpu_to_le64(src[i]); |
ccbe329b | 1176 | else |
9b6c2d2e | 1177 | dst[i] = cpu_to_le32(src[i]); |
ccbe329b DV |
1178 | } |
1179 | } | |
1180 | EXPORT_SYMBOL(bitmap_copy_le); | |
e8f24278 | 1181 | #endif |
c724f193 | 1182 | |
c42b65e3 AS |
1183 | unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) |
1184 | { | |
1185 | return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), | |
1186 | flags); | |
1187 | } | |
1188 | EXPORT_SYMBOL(bitmap_alloc); | |
1189 | ||
1190 | unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) | |
1191 | { | |
1192 | return bitmap_alloc(nbits, flags | __GFP_ZERO); | |
1193 | } | |
1194 | EXPORT_SYMBOL(bitmap_zalloc); | |
1195 | ||
1196 | void bitmap_free(const unsigned long *bitmap) | |
1197 | { | |
1198 | kfree(bitmap); | |
1199 | } | |
1200 | EXPORT_SYMBOL(bitmap_free); | |
1201 | ||
c724f193 YN |
1202 | #if BITS_PER_LONG == 64 |
1203 | /** | |
1204 | * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap | |
1205 | * @bitmap: array of unsigned longs, the destination bitmap | |
1206 | * @buf: array of u32 (in host byte order), the source bitmap | |
1207 | * @nbits: number of bits in @bitmap | |
1208 | */ | |
ccf7a6d4 | 1209 | void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits) |
c724f193 YN |
1210 | { |
1211 | unsigned int i, halfwords; | |
1212 | ||
c724f193 YN |
1213 | halfwords = DIV_ROUND_UP(nbits, 32); |
1214 | for (i = 0; i < halfwords; i++) { | |
1215 | bitmap[i/2] = (unsigned long) buf[i]; | |
1216 | if (++i < halfwords) | |
1217 | bitmap[i/2] |= ((unsigned long) buf[i]) << 32; | |
1218 | } | |
1219 | ||
1220 | /* Clear tail bits in last word beyond nbits. */ | |
1221 | if (nbits % BITS_PER_LONG) | |
1222 | bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits); | |
1223 | } | |
1224 | EXPORT_SYMBOL(bitmap_from_arr32); | |
1225 | ||
1226 | /** | |
1227 | * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits | |
1228 | * @buf: array of u32 (in host byte order), the dest bitmap | |
1229 | * @bitmap: array of unsigned longs, the source bitmap | |
1230 | * @nbits: number of bits in @bitmap | |
1231 | */ | |
1232 | void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits) | |
1233 | { | |
1234 | unsigned int i, halfwords; | |
1235 | ||
c724f193 YN |
1236 | halfwords = DIV_ROUND_UP(nbits, 32); |
1237 | for (i = 0; i < halfwords; i++) { | |
1238 | buf[i] = (u32) (bitmap[i/2] & UINT_MAX); | |
1239 | if (++i < halfwords) | |
1240 | buf[i] = (u32) (bitmap[i/2] >> 32); | |
1241 | } | |
1242 | ||
1243 | /* Clear tail bits in last element of array beyond nbits. */ | |
1244 | if (nbits % BITS_PER_LONG) | |
1245 | buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31)); | |
1246 | } | |
1247 | EXPORT_SYMBOL(bitmap_to_arr32); | |
1248 | ||
1249 | #endif |